Medical Marijuana No Better Than Placebo in Dementia Study

(HealthDay News) — Low-dose oral tetrahydrocannabinol (THC) may not ease the common behavioral symptoms that affect people with dementia, according to a small study published online May 13 in Neurology.

The study included 50 seniors with dementia. About half lived at home; the others were in care facilities. Marcel Olde Rikkert, MD, PhD, chair of geriatrics at the Radboud Alzheimer Center in Nijmegen, Netherlands, and colleagues randomly assigned them to take either 1.5mg of THC or a placebo pill three times daily, for three weeks. The researchers focused on two types of behavioral symptoms: agitation/aggression and wandering.

The researchers found that over three weeks, patients in both groups showed a small improvement, on average. But the THC group was no better off than the placebo group. The other positive news, said the researchers, is that THC seemed well-tolerated. They found no effects on memory or heart rate, and potential side effects such as sleepiness and dizziness were no more common in the medical marijuana group than the placebo group.

"The improvement in the placebo group was remarkable, as dementia is a progressive disease," Olde Rikkert told HealthDay. "The improvement might have been caused by the fact that the patients received a lot of support during the study, or to the placebo effect."